JP3383547B2 - Milling equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to the inside of a lumbar chamber,
A screw conveyor for equipping the outer periphery with screw blades for conveying the grains supplied to the polishing chamber toward the outlet of the polishing chamber, and a polishing unit for polishing grains conveyed by the screw conveyor. TECHNICAL FIELD The present invention relates to a grain refining device in which a polishing roll provided with a member in a part of the outer peripheral portion in the circumferential direction is integrally rotatable around a coaxial core by a common drive rotation shaft.

[0002]

2. Description of the Related Art In such a grain refiner, for example, a cylinder provided with, for example, two spiral screw blades on its outer peripheral portion as a screw conveying portion is relatively rotated on the outer peripheral surface of a rotary shaft body constituting a drive rotary shaft. With the external fitting in the state of blocking, a polishing roll provided with a polishing wheel, for example, as a polishing member in a state along the roll axis direction, in the grain transport direction from the screw transport unit of the rotary shaft body. The lower side portion is screwed and coupled by the rotation in the direction opposite to the driving rotation direction to integrally rotate around the coaxial core (see, for example, Japanese Patent Application Laid-Open No. 4-284854).

[0003]

However, in the above-mentioned prior art, there is a difference in polishing performance between the devices. Therefore, as a result of examining the cause, it was found that the position of the conveying blade end of the screw blade and the position of the grinding wheel for polishing and the like vary depending on the dimensions of each component and the assembly accuracy, which causes a difference in polishing performance between the devices. did.

The present invention has been made in view of the above circumstances, and an object thereof is to perform an appropriate polishing process without causing a performance difference between devices.

[0005]

According to the first aspect of the present invention, in the polishing chamber, the grains supplied to the polishing chamber are directed to the outlet of the polishing chamber by the screw blades provided on the outer peripheral portion of the rotating screw conveying section. The milling roll, which is transported and provided with a milling member in a part of the outer peripheral portion in the circumferential direction, is integrally rotated around a coaxial core by a drive rotation shaft common to the screw transporting unit, and is transported by the screw transporting unit to be terminated. The grains transferred from the to the polishing roll are polished by the polishing member positioned such that the interval along the circumferential direction between the screw blade and the conveying end portion of the screw blade is a set interval.

Therefore, by setting the above-mentioned set interval such that the grain conveyed from the terminal end of the screw blade to the milling roll hits the milling member with high probability, the grain is favorably milled by the milling member. Therefore, proper polishing processing can be performed without causing a performance difference in each device as much as possible.

According to a second aspect of the present invention, in the first aspect, the grain conveyed by the screw conveying section and transferred from the terminal end to the polishing roll is set at a distance along the circumferential direction from the conveying terminal end of the screw blade. The polishing is performed by a polishing member which is formed in a longitudinal shape at intervals and along the axial direction of the roll.

Therefore, the grain conveyed from the terminal end of the screw blade to the polishing roll hits the starting end of the longitudinal polishing member with a high probability along the axial direction of the roll and has a good probability of being polished while Using the entire width from the start end to the end of the polishing member, the polishing can be carried out efficiently, and the preferred means of claim 1 can be obtained.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the screw conveyor has a cylindrical rotary shaft having screw blades on an outer peripheral surface and an inner peripheral surface fitted on an outer peripheral surface of the drive rotary shaft. While being provided in a state in which relative rotation is blocked at a set rotation phase with respect to the drive rotation shaft, the circumferential interval between the polishing member and the transport terminal end portion of the screw blade is set to be a set interval. By the screwing screw portion in which the cut-out position is set, the polishing roller is screwed to the drive rotation shaft by the rotation in the direction opposite to the drive rotation direction and is integrally rotatably connected.

Therefore, the cylindrical rotary shaft equipped with the screw blades is mounted on the drive rotary shaft by, for example, a rotation stopping member or the like to prevent rotation at a set rotational phase and to be fitted externally, while driving the rotation of the polishing roller. When the screw is screwed and coupled to the shaft by the screwing portion, the distance between the polishing member and the conveying terminal end portion of the screw blade along the circumferential direction becomes the set distance, so that the device can be easily and quickly assembled. It is possible to obtain the preferred measures of claim 1 or 2.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the grain refiner comprises a supply unit A for supplying grains to be milled, and a supply unit A thereof.
The grain supplied from the lower inlet 1 is transferred to the upper outlet 2 (corresponding to the outlet of the polishing chamber) while the polishing unit 3 and the polishing unit 3 are provided for flowing and discharging the grains. The resistance imparting unit C configured to give resistance to the grain discharged from 2 by the resistor 32, the discharging unit D discharging the grain refined by the polishing unit B, and the grain in the polishing chamber 3 Ventilation part E that ventilates air for suctioning the bran separated from
Is configured as a main component.

The base 4 of the grain refiner will be described with reference to FIG. The base body 4 includes a base 4a, a shaft-supporting cylindrical portion 4c located on the base 4a with its axis oriented in the up-down direction, and a shaft support cylindrical portion 4c having an upper end coaxial with the base 4a. A cylindrical portion 4d for forming a spermatozoon that is continuous in a line, and an outer cylindrical portion 4b that is located on the base 4a and surrounds the cylindrical portion 4c for pivotal support and the cylindrical portion for forming a spermatozoon 4d. Configured.

The supply section A will be described with reference to FIG. The supply part A is provided with a grain supply path 23 connected to the receiving port 1 formed on the lower side of the peripheral wall of the cylindrical portion 4d for forming a spermatozoa, and rotatably supported in the grain supply path 23. Side feed screw 24 and its side feed screw 2
It is composed of a supply electric motor M2 for rotationally driving 4, a hopper 25 which is connected to the grain supply path 23, and a shutter 26 which is provided at an outlet of the hopper 25.

Based on FIG. 1 and FIG. 2, the polishing part B will be described. Inside of the polishing chamber 3, a screw conveying unit 14 having a screw blade 14b on the outer peripheral portion for conveying the grain supplied from the receiving port 1 to the polishing chamber 3 toward the discharge port 2, and the screw conveying unit thereof. A grinding wheel 15c (corresponding to a polishing member) for polishing the grains conveyed at 14 is provided around a coaxial core by a common drive rotation axis K with a polishing roller 15 provided in a part in the outer circumferential direction in the circumferential direction. It is provided so that it can rotate freely.

The drive rotary shaft K is a pair of upper and lower bearings 1.
7, a cylindrical driving shaft body 16 rotatably driven by a shaft supporting cylindrical portion 4c so as to be rotatably driven around a vertical axis, and is externally fitted to an upper extension side portion of the driving shaft body 16. And a cylindrical portion 16A screwed and coupled to the drive shaft body 16 at the lower end portion. Then, when the driving shaft 16 is rotationally driven by the electric motor M1 for polishing, the driving shaft 1
6 and the cylindrical portion 16A are configured to integrally rotate.

The screw conveying portion 14 has a cylindrical rotary shaft 1 having two spiral screw blades 14b on the outer peripheral surface and an inner peripheral surface fitted onto the outer peripheral surface of the cylindrical portion 16A.
As described below, 4a is provided in a state in which relative rotation is blocked with respect to the drive rotation axis K at a set rotation phase.

That is, the tightening ring 18 and the annular member 20 having an L-shaped cross section are screwed to the driving shaft 16 above the bearing 17 supporting the upper part of the driving shaft 16. Tighten the tubular rotary shaft 14a by inserting the anti-rotation screw 19 that is fastened and screwed and fixed to the tightening ring 18 into the notch ki formed in a part of the outer peripheral surface of the lower end of the tubular rotary shaft 14a. It is fixed to a set rotational phase with respect to the drive shaft body 16 via a ring 18.

A ring member 21 made of rubber is slidable on the upper surface of the protruding portion of the annular member 20 having an L-shaped cross section.
Is supported by the shaft-supporting cylindrical portion 4c, and seals the bottom side of the polishing chamber 3.

As shown in FIG. 3, the Hosei roll 15 is
A cylindrical roll main body 15a, a bottomed cylindrical lid 15b that is screwed and connected to the upper end opening of the roll main body 15a to close the upper end opening, and the outer peripheral surface of the roll main body 15a is equally spaced in the circumferential direction ( It is composed of two grindstones 15c respectively provided in the grooves formed at 180 ° intervals. That is, each whetstone 15c is formed in a longitudinal shape along the roll axis direction. A large number of ventilation holes 15h opening from the inside of the cylinder (the ventilation passage H) to the outer peripheral portion are formed in a row in the vertical direction in each of the portions of the roll body 15a corresponding to the grindstones 15c. . Further, the ventilation holes 15h in one row and the ventilation holes 15h in the other row are arranged so as to be located on the same diameter when viewed in the axial direction of the polishing roller 15.

Further, the seisei roll 15 has the cylindrical portion 1
6A is screwed by rotation in a direction opposite to the drive rotation direction of 6A and integrally rotatably connected. Specifically, the male screw portion Nm is formed on the outer peripheral portion of the upper end portion of the cylindrical portion 16A, while the cylindrical roll body 15 of the starch roll 15 is formed.
A female screw portion Nf is formed on the inner peripheral portion of the lower end portion of a, and the male screw portion Nm and the female screw portion Nf constitute a screw portion N for screwing between the polishing roller 15 and the cylindrical portion 16A.

Here, as shown in FIG. 4, Hosei roll 1
Positioning means 100 for positioning the grindstone 15c, the screw blade 14b, and the like is provided so that the circumferential interval between the grindstone 15c provided in No. 5 and the conveying end portion of the screw blade 14b becomes a set interval t. There is. Specifically, for screwing so that the screw-side starting end of the elongated grindstone 15c is located in the roll axis direction with a set distance t in the direction opposite to the rotation direction from the conveying end of the screw blade 14b. The cut-out position of the screw portion N is set and configured.

Then, as described above, in the state where the anti-rotation screw 19 fixed to the tightening ring 18 is inserted into the notch ki formed in the tubular rotary shaft 14a, the tubular rotary shaft 1
4a is externally fitted to the cylindrical portion 16A, and the female thread portion Nf of the polishing roller 15 is screwed into the male screw portion Nm of the cylindrical portion 16A, thereby connecting the polishing roller 15 to the cylindrical portion 16A, and
The cylindrical rotating shaft 14a of the screw transport unit 14 is sandwiched and fixed between the lower end surface of the polishing roll 15 and the upper end surface of the tightening ring 18. The screw blade 14b and the grindstone 1
In order to arrange 5c and 5c at the set interval t shown in FIG. 4, an adjusting plate having a predetermined thickness is sandwiched between the cylindrical portion 16A and the tightening ring 18 as necessary, and the cylindrical portion with respect to the drive shaft body 16 is provided. 16
Adjust the rotation position of A.

The spermatozoon forming body G forming the spermatozoon 3 has a cylindrical portion 4d for forming the spermatozoa which covers the screw conveying section 14.
And a bran removal cylinder F that covers the Hoshisei roll 15 and is removable. Further, the outer casing 6 is detachably attached to the upper end of the outer cylindrical portion 4b so as to surround the bran removing barrel F.

The bran removing cylinder F, the cylindrical portion 4d for forming the sperm chamber, the cylindrical portion 4c for supporting the shaft, the outer cylinder 6 and the outer cylindrical portion 4b.
A bran recovery chamber 7 is formed between the and. The exterior cylinder 6 is provided with a transparent member so that the bran recovery chamber 7 can be seen from the outside. The bran collection chamber 7 communicates with a fan chamber 4e formed by partitioning in the base 4a through a ring-shaped opening 4f.

It should be noted that the passage formed by the drive shaft 16, the cylindrical portion 16A, the cylindrical rotary shaft 14a, and the polishing inner roll 15 being connected in series is made to function as a ventilation path H. . The lower end opening of the drive shaft 16 is in an open state for ventilation of grain cooling air, which will be described later.

The bran removing cylinder F will be further described. As shown in FIGS. 3 and 5, in the bran removing cylinder F, the upper and lower ends of a plurality of groove type frames 8 arranged inward at equal intervals in the circumferential direction are connected by connecting blocks 9 respectively, and adjacent groove portions are connected. A screen member 10 as a porous member is provided so as to close each gap of the die frame 8, and a grindstone 11 is provided along the groove of each groove die frame 8. The screen member 10 includes
A large number of vent holes 10a are provided for discharging the bran peeled from the grain along with the polishing to the bran collection chamber 7.

In each of the connecting blocks 9, the one formed on one end side in the longitudinal direction of the bran removing cylinder F and the one formed on the other end side thereof in the longitudinal direction overlap each other. In this state, eight bolt insertion holes 9a are formed.

At the upper end of the cylindrical portion 4d for forming the spermatozoa,
Eight bolts 12 are used for the eight bolt insertion holes 9 of the bran removing cylinder F.
It is arranged and attached in the circumferential direction so that it can be inserted into a. Then, with the eight bolt insertion holes 9a of the bran removing tube F inserted into the eight bolts 12, the bran removing tube F is placed on the upper end of the cylindrical portion 4d for forming the lumbar sperm, and each bolt 12 A nut 13 is screwed onto the bran, and the bran removal cylinder F is attached to the cylindrical portion 4 for forming the lumber spermatozoa.
It is attached to d. That is, the bran removing cylinder F is attached to the bolt 12
Also, the nut 13 is detachably attached to the cylindrical portion 4d for forming the abscission chamber of the base body 4.

The resistance applying portion C and the discharging portion D are integrally formed, and the resistance applying portion C and the discharging portion D in the integrated state are
At the upper end of the bran removing cylinder F, with a bolt 30 and a nut 31,
It is configured to be detachably attached.

Next, the discharge section D will be described with reference to FIGS. 1, 2 and 5. In the discharge part D, a casing 28 for forming a discharge chamber is communicatively connected to the upper portion of the flanged cylindrical body 27, and a discharge chute 29 is communicatively connected to the casing 28.

The inner diameter of the flanged cylindrical body 27 is the bran removing cylinder F.
The outer diameter of the flange portion of the flanged cylindrical body 27 is substantially the same as the inner diameter of the outer casing 6. In the flange portion of the flanged cylindrical body 27, four bolt insertion holes 27a are formed in a state of being aligned with every other four of the eight bolt insertion holes 9a of the bran removing cylinder F. There is. A plurality of vent holes 27b are formed in the flange portion of the flanged cylindrical body 27.

Then, in a state where the four bolt insertion holes 27a of the flanged cylindrical body 27 are aligned with the four bolt insertion holes 9a of the bran removal pipe F, every other four bolt insertion holes 9a, a discharging portion D (resistance application described later) is performed. (Which is in an integrated state with the portion C) is placed on the bran removing cylinder F. Then, the bolts 30 are inserted through the series of bolt insertion holes 27a and bolt insertion holes 9a, and the nuts 31 are screwed into the respective bolts 30 to remove the discharge portion D from the bran removing tube F.
The upper end opening of the outer casing 6 is closed by the flange portion of the flanged cylindrical body 27. As described above, in the state where the flanged cylindrical body 27 is attached to the bran removing cylinder F, the upper opening of the flanged cylindrical body 27 functions as the discharge port 2 of the polishing chamber 3.

Next, the resistance applying portion C will be described with reference to FIGS. 1 and 6. The resistance applying portion C includes the resistor 3
2 in the guide portion 33a of the resistor support base 33 positioned in the flow direction (that is, the vertical direction) of the grain flowing from the inside of the polishing chamber 3 toward the discharge port 2 in the flow direction. A guide member is provided so as to be reciprocally movable along the guide member 34, and a receiving member 34 is provided by a rack 35 and a pinion 36 so that the vertical position with respect to the resistor body supporting base 33 can be adjusted and adjusted, and a coil spring 37 and a resistor body 32 are provided.
The receiving member 34 so as to urge the
Is provided and configured. Further, in the resistance applying portion C, the grain flowing out from the discharge port 2 is based on the vertical position of the resistor 32 with respect to the resistor support base 33, that is, the vertical position of the resistor 32 with respect to the discharge port 2. A flow rate display unit 38 for displaying the flow rate of particles is provided.

The resistor 32 is a cylindrical member for guide 32a guided by the guide portion 33a, and a truncated cone-shaped pressure plate rotatably connected to one end of the member by a bearing 32b. And 32c. The resistor support base 33 is attached to the upper portion of the casing 28, and the resistor support base 33 has a guide tubular member 3 for the resistor 32.
A cylindrical hollow guide portion 33a for fitting the 2a therein and guiding it in a sliding state is provided coaxially with the flanged cylindrical body 27. The resistor 32 is provided so that the guide tubular member 32a is fitted into the guide portion 33a so as to be reciprocally movable in the vertical direction.

Two peripheral notches s extending in the vertical direction are provided in the peripheral wall of the guide tubular member 32a so as to face each other. The rack 35 is attached to the receiving member 34 so that it faces one of the two notches s, and
A sliding contact portion 34a that is fitted into the other of the individual cutout portions s and is in sliding contact with the guide portion 33a is provided. And
With the receiving member 34 positioned inside the guide tubular member 32a, the sliding contact portion 34a is fitted into the cutout portion s, and the rack 35 is rotatably supported by the resistor support base 33. It is provided by meshing with the pinion 36,
By rotating the pinion 36, the position of the receiving member 34 can be changed and adjusted in the vertical direction with respect to the resistor support base 33.

The coil spring 37 is sandwiched between the spring receiving portion h at the lower end of the receiving member 34 and the spring receiving portion h of the guiding tubular member 32a inside the tube of the guiding tubular member 32a. The resistor 32 is provided so as to urge it downward, that is, in the direction toward the discharge port 2.

The support member 39 is attached to the guiding tubular member 32a of the resistor 32, and the three shaft members 40 are respectively inserted into the through holes 28a formed in the upper surface of the casing 28. The parts are fixed to the support member 39, and the respective upper ends are connected by the connecting member 41. This prevents the guide tubular member 32a from rotating around its axis.

The flow rate display section 38 is configured to indicate the graduation 38b attached to the resistor support base 33 with the indicating needle 38a attached to the connecting member 41.

Next, the resistance applying portion C configured as described above.
The action of will be described. The rack 35 attached to the receiving member 34 is linked to the pinion 36 on the resistor support base 33 side through the notch s of the guide tubular member 32a,
In addition, the sliding contact portion 34a of the receiving member 34 passes through the notch portion s of the guide tubular member 32a, and the resistor support base 33.
Since it is in sliding contact with the guide portion 33a, the resistor 32 and the receiving member 34 can be relatively moved in the flow direction. When the pinion 36 is rotated, the receiving member 34
However, the sliding contact portion 34a moves in the flow direction with the sliding contact portion 34a slidingly contacting the guide portion 33a of the resistor support base 33, and accordingly, the coil spring 37 urges the coil spring 37 toward the discharge port 2. The resistor 32 connected to the receiving member 34 moves in the flow direction by the guide of the guide portion 33a, and the position in the flow direction with respect to the discharge port 2 is adjusted. Thereby, the flow rate of the grain discharged from the discharge port 2 can be adjusted. Further, when the flow rate of the grain discharged from the discharge port 2 changes, the resistor 32 is guided by the guide portion 33a of the resistor support base 33 and moves in the flow direction according to the change. The fluctuation of the flow rate of the grain discharged from the discharge port 2 can be absorbed.

Next, the ventilation section E will be described with reference to FIG. A fan 22 is arranged in a fan chamber 4e formed by partitioning in the base 4a so that the bran collection chamber 7 is suctioned through the opening 4f. Then, when the fan 22 is operated, the air sucked from the lower end opening of the driving shaft body 16 as shown by the solid line arrow in FIG. , The ventilation hole 10a, the bran collection chamber 7, and the opening 4f are sequentially passed through, and discharged from the outlet 4g formed in the fan chamber 4e to the outside. The bran separated from is also discharged. Further, by the suction action of the fan 22, air is sucked from the outside through the ventilation holes 27b of the flanged cylindrical body 27 and allowed to flow along the inner surface of the exterior body 6, and the transparent portion of the exterior body 6 is covered with bran or the like. It is designed to prevent fogging.

[Another Embodiment] Next, based on FIG. 7, a cylindrical rotary shaft 14a having screw blades 14b on the outer peripheral surface thereof.
Another embodiment of the positioning means for providing the above in a relative rotation prevention state at a set rotation phase with respect to the drive rotation axis K will be described. That is, in this example, a portion corresponding to the tightening ring 18 is continuously provided at the lower end of the cylindrical portion 16A, and the detent screw 19 screwed and fixed to this portion is attached to the cylindrical rotary shaft 14a.
The cylindrical rotary shaft 14a is fixed to the set rotational phase relative to the cylindrical portion 16A by being inserted into the notch ki formed at the lower end of the cylindrical rotary shaft 14a. Then, by screwing the female threaded portion Nf of the Lusei roll 15 into the male threaded portion Nm of the cylindrical portion 16A, the Lusei roll 15 is connected to the cylindrical portion 16A, and the positions of the screw blade 14b and the grindstone 15c are shown in FIG. Setting interval t shown in
It will be positioned so that.

Although not shown, in the embodiment shown in FIG. 2 or 7, the notch ki on the cylindrical rotary shaft 14a side is not shown.
Instead of inserting the rotation stop screw 19 to prevent relative rotation, the cylindrical rotation shaft 14a may be directly fixed to the outer peripheral surface of the cylindrical portion 16A with a screw.

The number of the screw blades 14b provided in the screw conveying section 14 may be one, or three or more, other than the case of the two in the above embodiment.

Further, as in the above-described embodiment, the cylindrical cylindrical shaft 14a constituting the screw conveying section 14 is replaced by the drive rotating shaft K.
Rather than being externally fitted to the cylindrical portion 16A constituting the above, the cylindrical cylindrical shaft 14a is formed thick to transmit the driving force from the driving shaft body 16, and the cylindrical cylindrical shaft 14a is made to have the polishing roller 15a. May be screwed together.

In the above embodiment, the grinding stone 15c, which is a polishing member, is formed in a longitudinal shape along the longitudinal direction of the roll.
The shape is not limited to this, and may be formed in a longitudinal shape in a state of being inclined with respect to the roll axis. Alternatively, a grindstone having a rectangular shape or the like instead of the longitudinal shape may be arranged on the outer peripheral surface of the Hosei roll 15.

In the above-described embodiment, the present invention is applied to the vertical grain refining device configured to rotate and drive the screw conveying unit 14 and the polishing roll 15 around the vertical axis. However, other than the vertical grain refining device, for example, it can be applied to a horizontal grain refining device that rotationally drives the milling roll 15 and the like around a horizontal axis.

In the above embodiment, the present invention has been illustrated with respect to the grain refiner using the grindstone 15c as the polishing member. However, instead of the grindstone 15c, a brush for polishing rice is attached to the polishing roll 15 as the polishing member. It can also be applied to a grain refiner for polishing rice.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing the entire configuration of a grain refiner.

FIG. 2 is a vertical sectional side view showing the lumbar region.

FIG. 3 is a cross-sectional plan view of the Hakusei part.

FIG. 4 is a cross-sectional plan view showing the positional relationship between the polishing member and the screw blades.

FIG. 5 is a partially cutaway side view showing the lumbar region.

FIG. 6 is a vertical sectional side view of a resistance applying portion.

FIG. 7 is a vertical cross-sectional side view showing a polishing unit according to another embodiment.

[Explanation of symbols]

3 Shousei room 14 Screw conveyor 14a Cylindrical rotating shaft 14b screw blade 15 Hosei roll 15c Luminous material K drive rotation axis N screw part for screwing 100 Positioning means

Front Page Continuation (56) References Japanese Patent Publication 7-71637 (JP, B2) Japanese Patent Publication 7-24783 (JP, B2) Japanese Patent Publication 7-4539 (JP, B2) (58) Fields investigated (Int .Cl. ⁷ , DB name) B02B 1/00-3/14

Claims (3)

(57) [Claims] 1. A screw transporting unit having screw blades on an outer peripheral portion for transporting grains supplied to the polishing chamber toward the outlet of the polishing chamber, and a transporting unit in the screw transporting unit. The milling roll, which is equipped with a milling member for milling the coming grains in a part of the outer circumferential direction, is a grain milling device that is integrally rotatable around a coaxial core by a common drive rotation shaft. The grain refining device is provided with a positioning means for positioning the polishing member and the screw terminal end of the screw blade so that the interval along the circumferential direction is a set interval. 2. The polishing member is formed in a longitudinal shape along a roll axis direction, and the positioning means is provided between a screw-side starting end portion of the elongated polishing member and a conveying end portion of the screw blade. The grain refining device according to claim 1, wherein the grain refining device is positioned so that the interval along the circumferential direction is a set interval. 3. A cylindrical rotary shaft having the screw blade on the outer peripheral surface and having an inner peripheral surface externally fitted to the outer peripheral surface of the drive rotary shaft is set with respect to the drive rotary shaft in the screw transport section. It is provided in a state where relative rotation is blocked in a rotation phase, and the polishing roller is integrally rotatably connected to the drive rotation shaft by being screwed by rotation in a direction opposite to the drive rotation direction, and the positioning means. The cutting position of the screw part for screwing between the polishing roller and the drive rotary shaft is set such that the spacing along the circumferential direction between the polishing member and the conveying end portion of the screw blade is a set interval. The grain refiner according to claim 1 or 2, which is configured as follows.